The fine is for its short selling activities without securing underlying assets, the Financial Services Commission (FSC) said in a statement, noting the U.S.-based international investment bank's unit conducted short sales worth 40.1 billion won in May.

Naked short selling, which occurs when an investor sells stock that has not yet been borrowed, is illegal in South Korea. ($1 = 1,126.5500 won) (Reporting by Hayoung Choi, Ju-min Park; Editing by Muralikumar Anantharaman)